Various stereotactic devices used in neurosurgery utilize burr hole mounted systems which use anchor bolts threaded into the skull of a patient. The anchor bolt driver device of the present invention is constructed to engage and rotate the anchor bolts for insertion and removal in cooperation with a stereotactic frame.
Anchor bolt drivers are known, however various issues, difficulties and limitations still exist relating to anchor bolt drivers that are placed through a lumen of the bushing of a stereotactic frame which are typically vertical or nearly vertical in position. When the shaft of the anchor bolt driver travels through the stereotactic lumen to reach past its distal end adjacent the patient's skull, the doctor or other personnel needs to position the anchor bolt into the driver's socket. Typically little space exists between the distal tip of the stereotactic lumen and the patient's skull, thereby making the attachment process cumbersome, ergonomically awkward, and sometimes not possible due to the tight space constraints.
Having a socket that is a press fit on the anchor bolt driver's drive head may work as a short term solution but it is problematic to maintain tolerances of both the driver's socket and the anchor bolt. Additionally, for small scale drive heads that are only one or two millimeters in size, for example, the socket of the driver often wears quickly thereby loosening up the press fit mating feature between the socket and the drive head of the anchor bolt.
In summary, prior art anchor bolt drivers do not provide a consistent means to attach the anchor bolt to the driver socket for ease of use in a stereotactic process. The state of the art for bone screws or anchor bolts for human use is typically nonferrous material such as titanium or a polymer such as PEEK. These screws and bolts are typically non-magnetic so a magnetic socket is not an option for use.
The anchor bolt driver design of the present invention overcomes the shortcomings and limitations of the prior art. Further, because the structure is a one piece design, it makes sterilization via steam autoclave or STERRAD easier because health care professionals do not need to take apart the driver and thus do not need to reassemble it.